我正在写一个程序来控制CD驱动器。带来错误“对'mciSendCommandA @ 16'的未定义引用”和“未定义引用'winmain @ 16'"。请帮助消除错误 [英] Am writing a program to control CD drive. Brings errors "undefined reference to 'mciSendCommandA@16' " and " undefined reference to 'winmain@16' ". Please help eliminate errors

问题描述

#include <tchar.h>
#include <windows.h>
#include <mmsystem.h> // for MCI function

//link to winmm.lib (usually included in project setting)
#pragma comment(lib, "winmm")

void ControlCdTray(TCHAR drive, DWORD command)
{
	//Not used here, only for debug
	MCIERROR mciError=0;
	//flags forMCI command
	DWORD mciFlags=MCI_WAIT|MCI_OPEN_SHAREABLE|
	MCI_OPEN_TYPE|MCI_OPEN_TYPE_ID|MCI_OPEN_ELEMENT;
	
	//open drive device and get device ID
	TCHAR elementName[]={drive};
	MCI_OPEN_PARMS mciOpenParms={0};
	mciOpenParms.lpstrDeviceType=(LPCTSTR)MCI_DEVTYPE_CD_AUDIO;
	mciOpenParms.lpstrElementName=elementName;
	mciError=mciSendCommand(0,
	 MCI_OPEN, mciFlags, (DWORD_PTR)&mciOpenParms);
	
	//Ejecting or closing tray using device ID
	MCI_SET_PARMS mciSetParms={0};
	mciFlags=MCI_WAIT|command;//command is send by caller
	mciError=mciSendCommand(mciOpenParms.wDeviceID,
	MCI_SET, mciFlags, (DWORD_PTR)&mciSetParms);
	
	//close device ID
	mciFlags=MCI_WAIT;
	MCI_GENERIC_PARMS mciGenericParms={0};
	mciError=mciSendCommand(mciOpenParms.wDeviceID,
	 MCI_CLOSE, mciFlags,(DWORD_PTR)&mciGenericParms);
}
	//Eject drive tray
	void EjectCdTray(TCHAR drive)
	{
		ControlCdTray(drive, MCI_SET_DOOR_CLOSED);
	}
	
	//Retract drive tray
	void CloseCdTray(TCHAR drive)
	{
		ControlCdTray(drive,MCI_SET_DOOR_CLOSED);
	}
	int_tmain(int argc,_TCHAR* argv[])
	{
		EjectCdTray(TEXT('E')); //driveletter hardcoded
		CloseCdTray(TEXT('E'));
		return 0;
	}

推荐答案

显然是一些链接器或项目问题。我的提示是，您的构建目标的项目设置中存在一些不匹配。最简单的方法是启动一个新项目（使用正确的设置）并复制所有代码或将这些项目设置与您的项目设置进行比较。我猜你做了一个dll项目，但想要一个控制台解决方案。

It is clearly some linker or project issues. My tip is, that you have some mismatch in your project settings for your build target. The easiest way is to start a new project (with the correct settings) and copy all your code or compare such project settings with yours. I guess you made a dll project but want a console solution.

请注意

Please note

引用：

int_tmain（int argc，_TCHAR * argv []）

int_tmain(int argc,_TCHAR* argv[])

应该是

Should be instead

int _tmain(int argc,_TCHAR* argv[])

CPallini你的解决方案解决了winmain @ 16的问题。但是，这行代码仍然存在问题。我不知道出了什么问题。带来未定义的'mciSendCommandA @ 16'引用'



mciError = mciSendCommand（mciOpenParms.wDeviceID，MCI_CLOSE，mciFlags，（DWORD_PTR）& mciGenericParms）;

CPallini your solution solves the problem of winmain@16. However, this line of code is still problematic. I dont know what is wrong. Brings "undefined reference to 'mciSendCommandA@16'

mciError = mciSendCommand(mciOpenParms.wDeviceID,MCI_CLOSE, mciFlags,(DWORD_PTR)&mciGenericParms);

这篇关于我正在写一个程序来控制CD驱动器。带来错误“对'mciSendCommandA @ 16'的未定义引用”和“未定义引用'winmain @ 16'"。请帮助消除错误的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！